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991.
W. Hess 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1971,329(1):1123-1123
Ohne Zusammenfassung 相似文献
992.
993.
Does preoperative needle localization lead to an increase in local breast cancer recurrence? 总被引:1,自引:0,他引:1
Kopans DB; Gallagher WJ; Swann CA; McCarthy KA; White G; Hall DA; Wood WC 《Radiology》1988,167(3):667-668
Between 1978 and 1981, 74 women with nonpalpable breast cancer underwent surgery after localization guides were placed. In 72 patients, guides were introduced parallel to the chest wall; in two the needle was positioned anteroposteriorly under computed tomographic guidance. Fifty-six cases (76%) were infiltrating cancer; 13 (17%), intraductal cancers; two (3%), inflammatory; and three (4%), lobular carcinoma in situ. Surgery was not used to treat the latter five patients. In the remaining 69 women, 42 (61%) were treated by means of modified radical mastectomy; six (9%), total mastectomy; 12 (17%), local excision and radiation therapy; and seven (10%), local excision alone; exact therapy for two women (3%) was unknown. At a minimum follow-up of 5 years, none of the 67 women in whom the parallel approach was used had a local recurrence. The authors conclude that preoperative placement of guides parallel to the chest wall does not appear to increase the risk of local breast cancer recurrence. 相似文献
994.
Sclerosing cholangitis: CT findings 总被引:5,自引:0,他引:5
The value of computed tomography (CT) in the detection of primary sclerosing cholangitis (PSC) in the intrahepatic and extrahepatic biliary systems was assessed by comparing CT scans of 20 cases of PSC with cholangiographic findings. In 16 of 19 cases of extrahepatic duct disease demonstrated with cholangiography, CT demonstrated abnormalities of the common hepatic duct, or bile duct, including duct stenosis, mural nodularity, duct dilatation, wall thickening, and mural enhancement. CT demonstrated intrahepatic disease in all 20 cases, including duct dilatation, duct stenosis, pruning, and beading. CT was superior to cholangiography in characterization of the status of the intrahepatic duct system in 11 of 20 cases. In addition, CT demonstrated extrabiliary complications of PSC in 12 cases and superimposed cholangiocarcinoma in three cases. While cholangiography remains the standard for diagnosis and follow-up of PSC, CT can provide valuable information about the extent and complications of the disease. 相似文献
995.
D T Greenfield L J Greenfield M L Hess 《The Journal of thoracic and cardiovascular surgery》1988,95(5):799-813
Oxygen-derived free radicals and intracellular calcium overload have been implicated as mediators of myocardial ischemia/reperfusion injury. We hypothesized that free radical scavengers or calcium channel blockers could enhance the protection afforded the isolated, working rat heart by crystalloid cardioplegia against this type of injury at 37 degrees C. Hearts from 42 male rats in seven groups (n = 6) were studied in an isolated, working heart preparation measuring aortic flow (ml/min/gm dry wt), peak systolic pressure (mm Hg), coronary artery flow (ml/min/gm dry wt), and calculated coronary vascular resistance (dyne.sec.cm-5/gm dry wt). Creatine kinase and lactate dehydrogenase release were measured before ischemia and at various times during the postischemic reperfusion period. Time-matched control hearts (group 1) were perfused for 2 hours. After finding that 30 minutes of ischemia and 10 minutes of reperfusion (group 2) produced significant (p less than 0.01) functional impairment that was completely protected (group 3) by a preischemic bolus of St. Thomas' Hospital cardioplegic solution, we again found significant (p less than 0.01) functional impairment after 40 minutes of ischemia and 10 minutes (group 4) or 20 minutes (group 5) of reperfusion despite a preischemic bolus of St. Thomas' Hospital cardioplegic solution. Diltiazem (10 mg/L) plus St. Thomas' Hospital cardioplegic solution (group 6) did not significantly (p less than 0.01) enhance functional recovery. Addition of superoxide dismutase plus catalase (200 microns/ml) (group 7) produced marked improvement in functional recovery that did not differ significantly (p less than 0.01) from control results (group 1). The creatine kinase and lactate dehydrogenase data strongly supported the preceding functional data. Coronary flow and vascular resistance were not significantly (p less than 0.01) changed from control values in any group. We conclude that the addition of superoxide dismutase and catalase but not diltiazem to St. Thomas' Hospital cardioplegic solution can significantly enhance myocardial protection against normothermic ischemia/reperfusion injury. This implicates oxygen-derived free radicals as mediators of this type of injury. 相似文献
996.
Pregnancy itself poses risks of morbidity and mortality to even the young, healthy woman. The nature of these risks may vary from country to country and, within the United States, from state to state. Hemorrhage, eclampsia, and infection, in general, are common obstetric risks. One of the most important nonobstetric causes of maternal death, and the focus of this article, is heart disease. 相似文献
997.
998.
A 22-year-old woman was evaluated for multiple round shadowsin the lower parts of her lungs 相似文献
999.
Diagnosis of fistulae and sinus tracts in patients with Crohn disease: value of MR imaging 总被引:9,自引:0,他引:9
G Koelbel U Schmiedl M C Majer P Weber H Jenss K Kueper C F Hess 《AJR. American journal of roentgenology》1989,152(5):999-1003
To investigate the potential of MR imaging in the evaluation of sinus tracts or fistulae associated with Crohn disease, 17 patients with pelvic or abdominal fistulae or sinus tracts underwent MR imaging with multislice spin-echo techniques, 500/15 and 1600/22,80 (TR/TE). The presence of fistulae and/or sinus tracts was confirmed by contrast-enhanced CT (n = 17) and/or sonography (n = 8), sinography (n = 6), or barium studies (n = 4). In all but three cases the fistulae and extramucosal inflammatory abnormalities were shown by MR. T1-weighted images provided excellent delineation of the extension of the fistulae relative to sphincters and adjacent hollow viscera and showed inflammatory changes in fat planes. T2-weighted images showed fluid collections within the fistulae, localized fluid collections in extraintestinal tissues, and inflammatory changes within muscles. The supralevator and infralevator compartments were well defined on coronal images. Thus, the perirectal spread of fistulae and sinus tracts with respect to the levator ani could be demonstrated in all cases. Our results suggest that MR imaging is useful for the demonstration and evaluation of pelvic and abdominal sinus tracts or fistulae associated with Crohn disease. 相似文献
1000.
Francis Pau Cyrus Lee Angilene Cowles Shu-Ping Yang David L. Hess & Harold Spies 《Journal of neuroendocrinology》1998,10(1):21-29
Pulsatile secretion of hypothalamic gonadotropin-releasing hormone (GnRH) is suppressed by α-adrenergic antagonists in ovariectomized (OVX) rabbits, thus suggesting that initiation of GnRH pulses requires the presence of norepinephrine (NE) stimulation. Terminals of NE neurons are located in proximity with GnRH cells in the hypothalamus, including the arcuate nucleus-median eminence (AME) region. Synaptic NE molecules may be catabolized or transported back to NE terminals (i.e. reuptake) via specific NE transporter proteins (NET). Thus, the amount of synaptic NE acting on GnRH cells is a function of the rate of NE release, metabolism and reuptake. Hypothetically, the rise and fall of a GnRH pulse may be associated with the similar fluctuations of synaptic NE release and/or NET activity. To test this hypothesis, we examined the effects of AME administration of desipramine (DMI, a specific NET blocking drug) on GnRH release. First, we delivered 0.2–10 mM doses of DMI continuously for 1 h via an AME microdialysis (μD) system into intact male rabbits. We found that each AME-DMI infusion, between dosages of 1 mM and 10 mM, stimulated a GnRH pulse, and that the size of these GnRH pulses were proportional to the dosage of DMI. To confirm the specificity of DMI on NET, we measured catecholamine content in μD samples by HPLC. The temporal (60 min) DMI induced a pattern of NE release that included a rising limb within the first 20–30 min; although NE returned to baseline values within the period of DMI treatment. Neither epinephrine nor dopamine levels were changed by DMI. Second, a median dose of DMI (5 mM) was given by μD for 60 min in four separate rabbit models: gonadal intact females (F-INT), intact males (M-INT), gonadectomized females (F-GDX) and castrated males (M-GDX). Individual μD samples were measured for NE and GnRH. Regardless of gender or gonadal status, 5 mM of DMI concomitantly induced a pulse-like release of NE and GnRH. Furthermore, the response of GnRH to DMI was greater in GDX rabbits than in INT animals of both genders. Third, we administered DMI (5 mM) for 30 min via a push-pull perfusion (PPP) system during four repeated 90 min intervals, in either F-INT or ovariectomized (F-GDX) females, and measured GnRH in PPP samples. In both F-INT and F-GDX, each DMI challenge induced a GnRH pulse. In F-INT, all sequential DMI-induced GnRH pulses were nearly equal in size. In contrast, in F-GDX, the first DMI-induced GnRH pulse was greater than subsequent ones. Collectively, these observations are consistent with the concept of noradrenergic regulation of pulsatile GnRH release, and we conclude that the temporal activity of NET may be an integral part of the mechanism by which GnRH pulses operate. 相似文献